Evaporative fluid cooling apparatus



195-?v H. MALKOFF EVAPORATIVE FLUID COOLING APPARATUS 3 Sheets-Sheet 1Filed Oct. 19, 1948 :e. mi .6130 am @110 war man an @nu arm an anINVENTOR.

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Jan. 22, 1952 H. MALKOFF EVAPORATIVE FLUID COOLING APPARATUS 3Sheets-Sheet 2 Filed Oct. 19, 1948 IN VENTOR.

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v A i i %4 ATTORNEY? Jan. 22, 1952 MALKOFF 2,583,149

EVAPORATIVE FLUID COOLING APPARATUS Filed Oct. 19, 1948 3 Sheets-Sheet 5Patented Jan. 22, 1952 UNITED .STATES PATENT OFFICE EVAPORATIVE FLUIDCOOLING APPARATUS Hyman Malkofl, Trenton, 'N. J., assignor to KramerTrenton Company, Trenton, N. J., a corporation of New Jersey ApplicationOctober 19, 1948, Serial No. 55,280

9 Claims. (Cl. 62-139) This invention relates to evaporative fluidcooling apparatus which is designed to chill and, in the case of gasesto condense, fluids in pipe coils, or the like; the invention beingespecially adapted for embodiment in condensers of refrigeratingapparatus, although it is also adaptable to the cooling of liquids suchas water and oil in various types of machinery and industrial apparatus.

The invention is directed more particularly to means for circulating thecooling water through the apparatus, and has for an object to providesuch means which cause a high rate of circulation without correspondingincrease in power consumption.

Another object is to provide such an apparatus in which the water iscirculated by a driven impeller or the like and which includes means forpreventing the water acted upon by the impeller from being churned orswirled in a rotary direction.

Another object is to provide such an apparatus in which the water levelis automatically maintained by the supplying from an outside sourceothers inherent in the invention, are satisfactorily of small incrementsof fresh water to compensate for slight losses occurring duringoperation.

Another object is to provide such an apparatus which includes means forautomatically periodically removing a portion of the water which hasbeen recirculated with consequent increase in its salt concentration,together with automatic means for periodically supplying fresh water toreplace that which has been thus removed.

Another object is to provide such an apparatus in which the means forperiodically removing a portion of the water is of the syphon type, andthe means for supplying quantities of fresh water is governed by a valvewhich is controlled by the level of the water in the apparatus.

7 Another object is to provide such an apparatus in which the water iscaused to drop or rain upon the coil from a considerable number oforifices in a vessel located above the coil, the size of the saidorifices being sumcient to permit the water to pass therethrough as aliquid as distinguished from being atomized.

Another object is to provide such an apparatus which includes a powerdriven fan that promotes vaporization of part of the water precipitatedupon the coil and increases the chilling effect upon the fiuid withinthe coil.

A further object is to provide certain improvements in the form,construction and arrangement of the parts whereby a substantial increasein eificiency and economy in-operation is secured and the abovementioned objects, as well as attained.

Practical embodiments of the invention are represented in theaccompanying drawings in which:

Fig. 1 represents a partly broken away and partly sectional elevationlooking at the fan end of the apparatus, which is in the form of a unitadapted to be suspended from a ceiling;

Fig. 2 represents a partly broken away and partly sectional sideelevation of the same;

Fig. 3 represents a detail section taken in the plane of the lineIII-III of Fig. 1, looking in the direction of the arrows;

Fig. 4 represents a detail transverse section taken in the plane of theline IV-IV of Fig. 2;

Fig. 5 represents a view similar to Fig. 1, but showing a modified formof the apparatus;

Fig. 6 represents a view similar to Fig. 2, but showing the saidmodified form;

Fig. 7 represents a side elevation, partly broken away and partly insection, of a second modified form which is adapted for floorinstallation; 1

Fig. 8 represents an elevation, partly broken away and partly insection, taken at right angles to Fig.7; and

Fig. 9 represents a detail elevation, partly broken away and partly insection, showing a third modification which is also adapted for floorinstallation.

Referring to Figs. 1 to 4, the apparatus is presented in the form of aunit and has a casing which is preferably composed of metallic plates orpanels, such as galvanized steel, and includes a top 1, sides 2 and 3,and a face plate 4, the said parts being firmly secured to each other asby welding or riveting. Channel iron brackets 5 and 6 are fixed to thetop I, as by riveting or welding, and are designed to cooperate with anysuitable type of ceiling hangers for suspending the unit as a whole.

To the underside of the top I a water distributing pan 7, which may becomposed of sheet metal, is fastened, preferably by welding, and fromthe said pan depend apair of coil header plates 8 and 9, which aresuitably apertured to receive the bends of a pipe coil 50, which ispreferably composed of copper or aluminum tubing and consists of aplurality of sinuous sections having their upper ends fitted into theside of a fluid inlet pipe H and their lower ends fitted into the sideof a discharge pipe l2. It will be understood that the connectionbetween the coil sections and the pipes l I and ii is fluid tight, and

55 the said pipes are snugly fitted through holes in sides 2, 3, in anysuitable ,manner. ,.such as by welding or riveting. In the drawing thesaid element I3, I4, is illustrated as of unitary construction, but itwill be understoodcthati-t. may -,be composed of several parts suitablyfixed to each other.

The reservoir I3 extends across the full width of the front or faceplate of the casing and", at

the lower portion of one side thereof is fitted a small chamber I5,--whic h may ;be designated a ump return tank, which tank I5 is connectedto water distributing pan 1 by a-vertically disposed water delivery tubeI6, so that water may be forcedfrom tank .ISt pan' I :7 s v The bottomofpan 7 is,pe rforated -preferably in the form of alarge numberofnozzles II, which are preferably of sufficient; diameter, e. g., oneeighth of an inch or larger, so as topermitwater to pass therethroughwithout being; atomized, and it will be clear that water passing throughthe said nozzles will descend upon all parts of coil I0 and that thewaterpassing downwardly through and dripping from the coil will betrapped by the catch pan I4 and returned to the reservoir I3. 1-

Uprising from pump return tank l5 is a cylindrical pump housing lt andtheupper end of said housing is covered by-a base plate I9, which servesto support an'electric pump motor 20, the drive shaft 2i of which motorprojects down: wardly through housing I8 and carries at its lowerextremity a bladed impeller 22. QEixed in the housing I8 above theimpeller22 is a sleeve 23 which has a hub 24 that may, if desired, serveas a bearing for shaft 2|, although the shaft is so short as not torequire a bearing, and. a series of radial vanes 26, which latter areparallel with the a A si s ..m ie s al.ser s f h l s. 26 is formed'inthe wall of the pump housing I8 immediately above the sleeve 23, topermit the ingress ofw'ater.

The face plate 4 of .the unit casing is provided with a large centralaperture zl w ithin which is, positioned a fan 28 tha.t,is mounted on adrive shaft 29 oi an electric motor 30, which'latter is;

supportedby four bracket arms 3 I, thataresuitsably fixed to the motor,as indicated at 32, and

are secured to. the face plate as by bolts 33. It; will be understoodthat pump motor and fan,

motor 30 are connected to any suitable source or sources of electriccurrent, and it maybenoted that the said motors may be subject tomanual. control only,as,-by suitable switches '(notshowni. and/or thatthe operationof either or both may. be subject to automatic control bypressure or thermostatic switches in a manner whichis well understood bythose conversant with the re-; frigeration industry and is notillustrated herein: as it constitutes no part of the present invention.

At the end of the casing opposite the fan aresecured upper and lowersupports 34, 35, to which are fixed aseries of vertically disposedeliminator blades 36, which are of zigzag form in cross-section. asshown in Fig. 4, the .purposepf'thesaid,

blades being to separate entrained water globules from the air driventhrough the casing by the fan so that the said water may fall into catchpan (4 and be returned to reservoir I3.

A pipe 3'I leads from any suitable source of water supply to reservoirI3 and the said pipe is opened and closed by a valve 36, which isgovernedby a float 39, the construction of said float valve being amatter of such common knowledge among mechanics and engineers as to callfor no further explanation or description. A syphon tube 40 is alsofitted in the Wall of reservoir I3 fora purpose to be hereinafterdescribed and a water overflow pipe 4I pierces the bottom of the saidreservoir at 42 to provide against the maintenance of too high a levelof water therein.

, In operation, the reservoir is filled by supplying water through pipe31 until it reaches the level of the top of pipe M, at which time float39 will close valve 38. ,It will be understood that this fillingof-reservoir I3 also fills pump housing I8 through holes 26 aswell aspump return tank I5 and the lower part of-water delivery tube I6, thelevel of the water in housing I8 and tube I6 being the same as the levelin reservoir-I3. Pump motor 20 and fan. motor 30 are then set inoperation and impeller 22, driven by motor 20, will force water throughtank I5 and tubeiI 6 into pan 1, from which latter the water will raindown from nozzles I1 and thoroughly Wet coil- I0 therebeneath; the waterpassing through and dripping from the, coil being received in catch panI4 and returned by -,it to reservoir I3. The operation of fan motor 30will, of course, rotate fan 28 and thus drive a current of air throughcoil structure I6; and out through eliminator blades 36. As the waterdripping on the coil is of lower temperature than the fluid within thecoil andthe coil itself, some of the said water will be vaporized andthus serve to reduce the tem-' perature of the coil and the fluidcirculating therethrough. The, air current from the fan will facilitatethis action chiefly by its cooling eiTect upon the water which isfalling from the pan nozzles I1, and the blades 36 ofthe eliminator willserve to separate most of the globules of water which are entrained bythe current from the fan, causing the-same to precipitate into catch panI4 and be returned to reservoir 'I3. It will be observed thatpan(:extends over the space between fan 28 and coil I0, so that waterfalling from this portion of the pan will be carried by the air currentfrom the fan against the front and lower part of the coil that isadjacent the fan;

thus insuring that said portion of the coil is adequately wetted. 7

The foregoing operation will thus serve eiiectively to cool thecoil andthe fluid circulating therethrough with very little loss of Water. .This

is an important industrial economy, not only because water supply iscommonly metered and charged for, but also because there is frequently alimit ,tothe amount'of water which is available and also a limit, as byordinance, to the amount that can be discharged into sewage facilities.

the extent that it would occur in the case of smaller apertures, wouldcorrespondingly reduce:

the fall of water upon the coil.

A feature of great value-in-this -apparatus is.

"the circulating pump and associated parts'which already indicated, the

induce such a high rate of circulation of water that maximum heattransfer. achieved, with the further advantage that the rapidcirculation greatly minimizes the deposition upon the surface of thecoil of the salts and the like normally present in water, whichdeposition would materially reduce the effectiveness of the coil andrequire cleaning or repair thereof. It has been found that the vanes 25which are positioned above the impeller 22 are very effective inassisting the pumping actionin that they are stationary and prevent theimpeller action from. churning or rotating th 'water within the pump.housing I8; and it has also been discovered that the effectiveness ofthe pumping action is materially enhanced by positioning the impeller 22so that it projects into tank whereby its area of rotation is partlywithin the pum housing l8 and partly within the said tank 15. Thisprojection of the impeller into the tank I5 is preferably to the extentof about ten to thirty percent of the height of the impeller blades. Thefunctional importance of this positioning of the impeller is due mainlyto the fact that tank I5 is larger in cross section than and differs incross sectional shape from the pump housing l8.

Such loss of water as occurs during operation will be automaticallyreplaced by the action of float valve 38, 39, which will permit theinflow of additional water when the level in reservoir I3 is reduced. Itis, furthermore, occasionally desirable to drain off some of the waterfrom reservoir [3 in order to prevent too high concen- I trationof-salts in the water being recirculated through the apparatus. Thisdrawing off of a portion of the water from the reservoir l3 can beaccomplished by manually or automatically opening the electric circuitfrom the source of the water intermediate said pans will return to.reservoir [3 and raise the level of water in the latter to a heightabove the top of overflow tube 4i. Should the overflow tube becomeclogged, the syphon tube will at once become effective and water will besyphoned therethrough from reservoir [3 until the water level is broughtdown to the extremity of the syphon tube within the reservoir, at whichtime the syphon action will be broken and the position of float 39 willpermit the inflow of a new increment of water to the reservoir. Itshould be mentioned that the size of the syphon tube and the float valveshould be of such relative proportions that the syphon action willwithdraw water from the reservoir more rapidly than it is suppliedthereto through the float valve.

It is desirable that the pump motor and the fan motor 30 have separatecontrols so that the pump motor can be stopped not only for the purposejust described but also in order that the water circulation may bestopped while the air circulation is continued when temperatureconditions or operating conditions are such that the apparatuseffectively performs its cooling function under the influence of the aircurrent alone. And in some cases the reverse may be desired, i. e., thatthe fan be stopped while the pump continues in operation. In thisconnection, it will,

of course, be understood that condensers of this type, especially whenused in refrigerating systems, are normally required to operateintermittently rather than continuously; and that, as

efiiciency is the sleeves action of both the pump motor and the fanmotor maybe subjected to manual control and/or to automatic control bypressure or temperature actuated switches.

Turning now to the modified form of the invention shown in Figs. 5 and6, the constructional parts are the same as hereinabove described inconnection with theform shown in Figs. 1 to 4 with the exception of thepump mechanism whichis somewhat different in construction andarrangement and operates on the wa ter pulling principle rather than onthe pushing or thrusting principle.

. In this" form of Figs. 5 and'fi, the cylindrical pump housing isdenoted by 43 and it uprises directly from the. bottom of reservoir l3and extends substantially to the top of the casing where his capped bya. T-coupling 44, the horizontal branch 45 of which is suitablylconnected, as by bolted flanges, to a mouth piece-'46 on the waterdistributing pan T. An electric'motor 41, which corresponds to the motor20 of the form shown in Figs. 1 to 4, has its base 48 resting oncoupling 44, and the motor drive shaft 49 extends downwardly within pumphousing 43 almost to the bottom thereof. Three impellers denoted by 50,5t and 52, which are similar to impeller 22, are fixed to shaft 45; andthree sleeves 53, 54, 55,

which are like sleeve 23 with its hub and vanes,

are rigidly positioned within housing 43 closely above impellers 5!], 5|and 52 respectively. Two sets of circumferential holes 56 and 5'! areformed through pump housing 43 below impeller 50. As this shaft 49 isquite long, it is desirable that the hub of at least one sleeve, e. g.,54, be of such size as to serve as a bearing therefor.

In the operation of this form of the invention shown in Figs. 5 and 6,the reservoir 13 is supplied with water as heretofore described inconnection with the form shown in Figs. 1 to 4 and the pump motor 47, aswell as the fan motor 30, are started. The rotation of the shaft 49 ofmotor 6'! causes impeller 50 to draw water up within pump housing 43until the water reaches the height of impeller 5 l, at which time thelatter adds its drawing effect on the water, which continues to be drawnup within the pump housing until it reaches impeller 52, at which timeall three impellers are acting on the column of water and force the sameinto the water distributing pan 1, whence it rains down upon the coiland is in the main returned to the reservoir i3 as heretofore describedin connection with the form shown in Figs. 1 to 4-. It will be observedthat 54, 55, with their radiating vanes, are located above theimpellers, as in the case of the form shown in Figs. 1 to 4,notwithstanding the column of water is movin upward in pump housing 43of the modified form of invention shown in Figs. 5 and 6 instead ofdownward as in the previously described form. However, the effect of thevanes in the said sleeves is the same in the form shown in Figs. 5 and 6as in the first described form and the operation of the invention andits functional effects are also the same. The ceiling brackets 58, 59,which are secured to the top of the apparatus casing in the form shownin Figs. 5 and 6, are different in shape from the brackets shown inFigs. 1 and 2 in order to space pump motor 41 from the ceiling. It maybe added that the pump motor and fan motor of the form shown in Figs. 5and 6 may be manually and/or automatically controlled, as set forth inthe; description of the preceding form of theinvention'f i Referring now'to. the second modified term .01 the invention which is, shown; in,Figs; 7 and; 8. this embodiment is designed for floor installation anddiffers in a number of respectsfromrthe previously describedforms,although -;the,;.'pumping mechanism, which is the most important featureof the invention, is similar to that;of:.iligs. lto In this modifiedform OLFigsfliy. and 8,'ithe casing is oblong ,in,;crosss;s ection. andicomprises 'a front 60, a, back :6|,.sides 611;;63, and; bottom 64, whichare preferably composed;.o materials such as galvanized s heet,platessecured together in any suitable manner, as ,bsrx-Wldhrgmrriveting; thebottom being provided :Wlth ;legs;-65, preferably of angle iron. r; a; 11;

; The upper part of the casing houses a. pfl liof blowers 66, 66,whichmay be of any; wellknown or approved form. and besecure withinil he0&3? ing in any appropriate manner; the .fans of the said blowers (notshown) being rotatedby va shaft 61, which is driven by a motor 68,carried by a bracket 60, throughbelt andpulley--mecha-. nism 10. H 1.iz; l

A set of eliminator blades H is fixed in' the casing below the blowers;by angle irons 12 that are fastened to the sides .62, :63, of. thecasing; and a coil '53, which has aninlet vpipeJ'T-and a discharge pipe15, is mounted about midway be-, tween the top and bottom'ofthejcasingbyheader plates 16, H, which-extendtransversely .of the casing and aresuitably attached to its frontand back. g1,

The water circulating means which, as already indicated, is similar: tothatshowndn Figs.;1 to '3, includes a cylindrical pump housing 18; that-up-'. rises from a reservoir '19 which is formed in the lowerpart ofthe casing. The housingzis provided with a series of waterinlet holes.80 andra vane sleeve 8|, which is ,likesleeve, 23,: 24,25, and is fixedin the housing below thesaid'holes. 1A motor 82 surmounts housing 18 andits shaft 83 carries an impeller 84 which is located at the bottom ofthe housing and extends; partly, into a pump return tank 85 that isconnected-with one end of the pump housing.= A water ;delivery tube 86is connected with the other end of. tank 85 and extends upwardly'withinthe casing toa point intermediate the eliminator and the coil, where itconnects with amanifold ill-from which project laterally a set, of.closedend .water dis tributing pipes 88 that are providedwvithi per-.1forated nozzles along their lower.- surfaces, corresponding to nozzlesI! shown in Figs. 1 and 2.

If desired, the tube 86 may be securedby-any suitable means to the side62 of the casingrand, the pipes 88 may also be secured to each other andto the front 60 and back 6l-of the casing by brackets or otherequivalent means..'; The

reservoir 79 has an overflow pipe'89 which pierces? its bottom at 90, awater inlet pipe '9I,='a float valve 92, and-a 'syphon tube 93, whichare similar to the corresponding partsqshownrin Fig; 1. The front of thecasing is provided witha'mctalair inlet grill 94 which permits airtOibBdrawn into the casing, past the coil, water distributing pipes andeliminator, and be ejected at the top of the casing through the blowermouths.

The operation or functioning. of; this formof the invention shown inFigs. 7 and 8;. is generally the same as that hereinabove describedexcept that the suction generated by the blowersfifi, 66,; issubstituted ior'the aiiystream-ygeneratedby. the fan;28, while thewaterfalling from the dis r bu ep es tee dr n fr m; t 'c i l3;-- andeliminator H passes directly int qthe reserg;

NONI--19 instead :ofbeing-caugh iniahpan and returned to theI'eSeIVOiIH; Asin the caseof the previously described forms, .the motors.68z-and 82 of this ,second modified form may. ,be. independentlycontrolled manually and/or automati .callyr; a v .The third modifiedform. of vthe invention. .Which isaillustrated in Fig. 9, differs from.the form shown in Figsfll and 8 insubstantiallythe same-way that theform shown in Figs. 5 and 6 differs from the form shown'in Figs; 1"to=4,i.;e;, the;water pump ofthe form shown in :Figz'Q operates-on thepulling rathenthanon thepuslring -or thrusting principle.- In thisv formthe pump housing is marked 95 and itszlower end positioned in thereservoir l0 has ,lLWOzSGbSu'Qf Vi/M161 .inlet holes 96, 91..The;.upper. endofthe housing: is connected, by a T-coupling vtil iwiththeg-mouth of ,manifold 81'. and the pump motor, here marked I00,surmounts coupling 98 while its shaft NH. projects downwardly throughthree vane sleeves I02, N3, 104, that arefixed withinI housing and arelike sleeve 23, 24, 25, with at least one sleeve, e. g., I03, servingaspa bearing for the shaft. Threeimpellers I05, 106. 101, are fixed onshaft l0! below said sleeves and their action-when rotated by motor I00,is. like that of impellers 50, 5| and 52, as. describedin connectionwith the form of the invention shown inFigs. 5 and 6. With reference toall the forms of the invens tion, it will be seen that it provides fora-very eflicient and rapid circulation and recirculation of water, aswell as efficient cooling of the fluid within the evaporator, thefunction or result being accomplished with great economy of water andpower and with avoidance. of cloggin the water distributing elements and:the formation ofundesirable deposits upon thecoil; while suchadditional supply of fresh water as is desirable either for the purposeof replenishing the slight loss, or diluting the salt concentration, isautomatically furnished.

It will be understood that various changes may be resorted to in theform, construction, material and arrangement of the parts withoutdeparting from the spirit or scope of the invention; and hence I do notintend-to be limited to details herein shown or describedexcept as theymaybe included-in the claims or be required by disclosures of the priorart.

-What I claim is:

1. Apparatus of the character described comprising, a coil, a waterreservoir, a conduit for distributing water from the reservoir to theouter surface of the coil, and pumping mechanism adapted to cause waterto flow from the reservoir through said conduit, said pumping mechanismcomprising, a housing having a water inlet in the side thereof, a motorvdrive shaft within the housing, an impeller fixed to the shaft, and atleast one vane positioned within the housing adjacent, the impellerandlying in a plane substantially, parallel to the longitudinal axis ofthe shaft to resist swirling of the Water within the housing when theimpellenis" rotated.-

2. Apparatus of the character described comprising, a coil, a waterreservoir, a conduit for distributing water from the reservoir to theouter surface of the coil, and pumping mechanism adapted to cause waterto flow from the reservoir through said conduit, said pumping mechanismcomprising, a housing having a water inlet in the side thereof, amotorlocated at the top of the housing, a drive, shaft extending from themotor downwardly within the housing, an impeller fixed to the shaft, andat least one vane positioned within the housing adjacent the impellerand lying in a plane substantially parallel to the longitudinal axis ofthe shaft to resist swirling of the water within the housing when theimpeller is rotated.

3. Apparatus of the character described comprising, a coil, a waterreservoir, a conduit for distributing water from the reservoir to theouter surface of the coil, and pumping mechanism adapted to cause waterto flow from the reservoir through said conduit, said pumping mechanismcomprising, a housing having a water inlet in the side thereof, a tankat the lower end of the housing, a motor drive shaft within the housing,and an impeller fixed to the shaft and positioned partly within thehousing and partly within the tank.

4. Apparatus of the character described comprising, a coil, a waterreservoir, a conduit for distributing water from the reservoir to theouter surface of the coil, and pumping mechanism adapted to cause waterto flow from the reservoir through said conduit, said pumping mechanismcomprising, a housing having a water inlet in the side thereof, a tankat the lower end of the housing, said tank being of greater crosssectional area than the housing, a motor drive shaft within the housing,and an impeller fixed to the shaft and positioned partly within thehousing and partly within the tank.

5. Apparatus of the character described comprising, a coil, a waterreservoir, a conduit for distributing water from the reservoir to theouter surface of the coil, and pumping mechanism adapted to cause waterto flow from the reservoir through said conduit, said pumping mechanismcomprising, a housing having a water inlet in the side thereof, a tankat the lower end of the housing, said tank being of greater crosssectional area than and differing in cross sectional shape from thehousing, a motor drive shaft within the housing, and an impeller fixedto the shaft and positioned partly within the housing and partly withinthe tank.

6. Apparatus of the character described comprising, a coil, a waterreservoir, a conduit for distributing water from the reservoir to theouter surface of the coil, and pumping mechanism adapted to cause waterto flow from the reservoir through said conduit, said pumping mechanismcomprising, a housing having a water inlet in the side thereof, a tankat the lower end of the housing, said tank being of greater crosssectional area than the housing, a motor drive shaft within the housing,and an impeller fixed to the shaftand positioned partly within thehousing and partly within the tank, the projection of the impeller intothe tank being less than one half the vertical height of its blades.

7. Apparatus of the character described comprising, a coil, a waterreservoir, a conduit for distributing water from the reservoir to theouter surface of the coil, and pumping mechanism adapted to cause waterto flow from the reservoir through said conduit, said pumping mechanismcomprising, a housing having a water inlet in the side thereof, a tankat the lower end of the housing, said tank being of greater crosssectional area than and differing in cross sectional shape from thehousing, a motor drive shaft within the housing, and an impeller fixedto the shaft and positioned partly within the housing and partly withinthe tank, the projection of the impeller into the tank being less thanone half the vertical height of its blades.

8. Apparatus of the character described comprising, a coil, a waterdistributor located above the coil, a water reservoir, a conduitconnecting the distributor with the reservoir, a pump adapted to causewater to flow from the reservoir to the distributor, and means forforcing a current of air to and through the coil structure in adirection at an angle to the direction in which water from thedistributor traverses the coil, the water distributor being sopositioned as to extend over an area in front of the face of the coiltoward which the air current moves so that water falling from the saidextension of the distributor will be carried by the air current againstthe said face of the coil.

9. Apparatus of the character described comprising, a coil, a waterreservoir, a conduit fordistributing water from the reservoir to theouter surface of the coil, and pumping mechanism adapted to cause waterto flow from the reservoir through said conduit, said pumping mechanismcomprising, a tank having a water inlet and a water outlet, a powerrotated impeller at the water inlet of the tank, and at least one vanepositioned at the upstream side of the impeller to resist swirling ofthe water drawn toward the impeller by its rotation.

HYMAN MALKOFF.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,428,661 Richardson Sept. 12,1922 1,861,158 Hilger May 31, 1932 2,221,530 Strang Nov. 12, 19402,259,541 Ballard Oct. 21, 1941 2,291,937 Young Aug. 4, 1942 2,379,932Schoepfiin July 10, 1945 2,509,031 Bockmeyer May 23, 1950 FOREIGNPATENTS Number Country Date 560,319 France Oct. 2, 1923 839,815 FranceApr. 3, 1939

